Engelmaier Solder
Joint Fatigue Life Assessment in DfRSoft
Engelmaier Model -
DfRSoft includes a solder joint/BGA fatigue shear stress and
life assessment using the historical Engelmaier model. To use the model,
Step 1 we use the DfRSoft library to find the CTE mismatch between the
component and the board or this can be manually entered. Step 2 is to
input the size of the BGA (distance to neutral point) explained in
DfRSoft. Then enter the solder joint height based on historical
information in DfRSoft or the user enters this. Finally we enter the
delta Temperature the component is exposed to either in the field or in test. DfRSoft also allow the user to estimate the impact of underfill.
The output is the Engelmaier
Fatigue Number of Cycles to Fail
and a Shear strain risk assessment. The user also has available data from published
sources on cycle life from such inputs so the user can compare results
to their situation.
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